Prospective Evaluation of the Nature, Course, and Impact of Acute Sleep Abnormality After Traumatic Brain Injury

Sleep Disruptions in Hospitalized Adults Sustaining a Traumatic Brain Injury: A Scoping Review

OBJECTIVE

Adults sustaining a traumatic brain injury (TBI) are at risk of sleep disturbances during their recovery, including when such an injury requires hospitalization. However, the sleep-wake profile, and internal and external factors that may interfere with sleep initiation/maintenance in hospitalized TBI patients are poorly understood. This review aimed to: (1) identify/summarize the existing evidence regarding sleep and sleep measurements in TBI adults receiving around-the-clock care in a hospital or during inpatient rehabilitation, and (2) identify internal/external factors linked to poor sleep in this context.

METHODS

A scoping review was conducted in accordance with the PRISMA Scoping Review Extension guidelines. A search was conducted in MEDLINE, PsycINFO, CINAHL, and Web of Science databases.

RESULTS

Thirty relevant studies were identified. The most common sleep variables that were put forth in the studies to characterize sleep during hospitalization were nighttime sleep time (mean = 6.5 hours; range: 5.2-8.9 hours), wake after sleep onset (87.1 minutes; range: 30.4-180 minutes), and sleep efficiency (mean = 72.9%; range: 33%-96%) using mainly actigraphy, polysomnography, and questionnaires (eg, the sleep-wake disturbance item of the Delirium Rating Scale or the Pittsburgh Sleep Quality Index). Twenty-four studies (80%) suggested that hospitalized TBI patients do not get sufficient nighttime sleep, based on the general recommendations for adults (7-9 hours per night). Sleep disruptions during hospitalization were found to be associated to several internal factors including TBI severity, cognitive status, and analgesia intake. External and modifiable factors, such as noise, light, and patient care, were consistently associated with sleep disruptions in this context.

CONCLUSION

Although the literature on sleep disturbances in hospitalized TBI patients has been increasing in recent years, many gaps in knowledge remain, including phenotypes and risk factors. Identifying these factors could help clinicians better understand the multiple sources of TBI patients' sleep difficulties and intervene accordingly.

Strategy and Philosophy for Treating Pain and Sleep in Disorders of Consciousness

Despite the evolving practice of brain injury medicine, consciousness remains enigmatic. Most patients with disorders of consciousness have disordered sleep and return of normal sleep architecture is essential to the emergence of consciousness and the healing brain. In this article we lay a framework for understanding the emergence of consciousness in brain-injured patients. We then explore ways to use that framework to evaluate and tailor treatment of sleep and pain in patients with disorders of consciousness. Although more research is needed to empower better treatment in the future, validated tools now exist for evaluation of emergent consciousness, pain, and sleep.

The growing gap: A study of sleep, encoding, and consolidation of new words in chronic traumatic brain injury

Word learning is an iterative and dynamic process supported by multiple neural and cognitive systems. Converging evidence from behavioral, cellular, and systems neuroscience highlights sleep as an important support for memory and word learning over time. In many lab-based word learning experiments, participants encode and subsequently retrieve newly learned words in a single session. These designs are inadequate to capture the full dynamic word learning process, making them less ecologically valid. Single timepoint studies also limit investigation of the role of behavioral and lifestyle factors, like sleep, in supporting word learning over time. Adults with a history of traumatic brain injury (TBI), who commonly exhibit deficits in the memory systems that support word learning and report concomitant sleep disturbance, provide a unique opportunity to examine the link between memory, sleep, and word learning. Here we examined word learning over time and the influence of sleep on short- and long-term word recall in 50 adults with chronic moderate-severe TBI and 50 demographically matched neurotypical peers. We used a randomized within-participant crossover design to assess immediate encoding of new words and the consolidation of those words over time across intervals that did or did not involve sleep. Participants completed this study over the course of two weeks in their own homes to capture the iterative, dynamic process of real-world word learning. We also measured sleep in free living conditions using actigraphy throughout the experiment. Participants with TBI exhibited a word learning deficit that began at encoding and persisted across time. Critically, this deficit grew over the course of the week. The performance gap between groups was larger at the 1-week post-test than the immediate post-test, suggesting deficits in both encoding and consolidation of new words in individuals with TBI. Participants with and without TBI remembered more words when they slept after learning. Ecologically valid research designs that examine the relationship between memory, sleep, and word learning over time promise to advance mechanistic accounts of word learning and improve the long-term retention of new words in individuals with and without brain injury.

A comparison of agreement between actigraphy and polysomnography for assessing sleep during posttraumatic amnesia

STUDY OBJECTIVES

Sleep disturbance often emerges in the early recovery phase following a moderate to severe traumatic brain injury, known as posttraumatic amnesia. Actigraphy is commonly employed to assess sleep, as it is assumed that patients in posttraumatic amnesia (who display confusion, restlessness, and agitation) would better tolerate this measure over gold-standard polysomnography (PSG). This study evaluated the agreement between PSG and actigraphy for determining (sleep/wake time, sleep efficiency, sleep latency, and awakenings) in patients experiencing posttraumatic amnesia. It also compared the epoch-by-epoch sensitivity, specificity, and accuracy between the Actigraph device's 4 wake threshold settings (low, medium, high, and automatic) to PSG.

METHODS

The sample consisted of 24 inpatients recruited from a traumatic brain injury inpatient rehabilitation unit. Ambulatory PSG was recorded overnight at bedside and a Philips Actiwatch was secured to each patient's wrist for the same period.

RESULTS

There were poor correlations between PSG and actigraphy for all parameters (Lin's concordance correlation coefficient = < 0.80). The low threshold displayed the highest correlation with PSG for wake and sleep time, albeit still low. Actigraphy displayed low specificity (ranging from 17.1% to 36.6%). There appears to be a greater disparity between actigraphy and PSG for patients with increased wake time.

CONCLUSIONS

Actigraphy, while convenient, demonstrated poorer performance in determining sleep-wake parameters in patients with significantly disturbed sleep. Ambulatory PSG can provide a clearer understanding of the extent of sleep disturbances in these patients with reduced mobility during early rehabilitation. Study findings can help design future protocols of sleep assessment during posttraumatic amnesia and optimize treatment.

CITATION

Fedele B, McKenzie D, Williams G, Giles R, Olver J. A comparison of agreement between actigraphy and polysomnography for assessing sleep during posttraumatic amnesia. J Clin Sleep Med. 2022;18(11):2605-2616.

The Utility of the Patient Health Questionnaire (PHQ-9) Sleep Disturbance Item as a Screener for Insomnia in Individuals With Moderate to Severe Traumatic Brain Injury

OBJECTIVE

To examine the utility of the sleep disturbance item of the Patient Health Questionnaire-9 (PHQ-9) as a screening tool for insomnia among individuals with moderate to severe traumatic brain injury (TBI).

SETTING

Telephone interview.

PARTICIPANTS

A sample of 248 individuals with a history of moderate to severe TBI participated in an interview within 2 years of their injury.

DESIGN

Observational, cross-sectional analysis.

MAIN MEASURES

The PHQ-9 was administered along with the Insomnia Severity Index, Pittsburgh Sleep Quality Index, Sleep Hygiene Index, Epworth Sleepiness Scale, and the Insomnia Interview Schedule.

RESULTS

Receiver operating characteristic curve analysis was conducted for the PHQ-9 sleep item rating against a set of insomnia criteria to determine an optimal cutoff score. A cutoff of 2 on the PHQ-9 sleep item maximized sensitivity (76%) and specificity (79%), with an area under the curve of 0.79 (95% CI, 0.70-0.88). The 2 groups formed using this cutoff differed significantly on all sleep measures except the Epworth Sleepiness Scale.

CONCLUSIONS

The PHQ-9 sleep item may serve as a useful screener to allow for detection of potential sleep disturbance among individuals with moderate to severe TBI. Those who screen positive using this item included in a commonly used measure of depression can be prioritized for further and more comprehensive assessment of sleep disorders.

The Effect of Traumatic Brain Injury on Sleep Architecture and Circadian Rhythms in Mice—A Comparison of High-Frequency Head Impact and Controlled Cortical Injury

Simple Summary

Traumatic brain injury (TBI) is a significant risk factor for the development of sleep and circadian rhythm impairments. In order to understand if TBI models with different injury mechanism, severity and pathology have different sleep and circadian rhythm disruptions, we performed a detailed sleep and circadian analysis of the high-frequency head impact TBI model (a mouse model that mimics sports-related head impacts) and the controlled cortical impact TBI model (a mouse model that mimics severe brain trauma). We found that both TBI models disrupt the ability of brain cells to maintain circadian rhythms; however, both injury groups could still maintain circadian behavior patterns. Both the mild head impact model and the severe brain injury model had normal amount of sleep at 7 d after injury; however, the severe brain injury mice had disrupted brain wave patterns during sleep. We conclude that different types of TBI have different patterns of sleep disruptions.

Abstract

Traumatic brain injury (TBI) is a significant risk factor for the development of sleep and circadian rhythm impairments. In this study we compare the circadian rhythms and sleep patterns in the high-frequency head impact (HFHI) and controlled cortical impact (CCI) mouse models of TBI. These mouse models have different injury mechanisms key differences of pathology in brain regions controlling circadian rhythms and EEG wave generation. We found that both HFHI and CCI caused dysregulation in the diurnal expression of core circadian genes (Bmal1, Clock, Per1,2, Cry1,2) at 24 h post-TBI. CCI mice had reduced locomotor activity on running wheels in the first 7 d post-TBI; however, both CCI and HFHI mice were able to maintain circadian behavior cycles even in the absence of light cues. We used implantable EEG to measure sleep cycles and brain activity and found that there were no differences in the time spent awake, in NREM or REM sleep in either TBI model. However, in the sleep states, CCI mice have reduced delta power in NREM sleep and reduced theta power in REM sleep at 7 d post-TBI. Our data reveal that different types of brain trauma can result in distinct patterns of circadian and sleep disruptions and can be used to better understand the etiology of sleep disorders after TBI.

Sleep Spindles and K-Complexes Are Favorable Prognostic Biomarkers in Critically Ill Patients

SUMMARY

In this narrative review, we summarize recent research on the prognostic significance of biomarkers of sleep in continuous EEG and polysomnographic recordings in intensive care unit patients. Recent studies show the EEG biosignatures of non-rapid eye movement 2 sleep (sleep spindles and K-complexes) on continuous EEG in critically ill patients better predict functional outcomes and mortality than the ictal-interictal continuum patterns. Emergence of more complex and better organized sleep architecture has been shown to parallel neurocognitive recovery and correlate with functional outcomes in traumatic brain injury and strokes. Particularly interesting are studies which suggest intravenous dexmedetomidine may induce a more biomimetic non-rapid eye movement sleep state than intravenous propofol, potentially providing more restorative sleep and lessening delirium. Protocols to improve intensive care unit sleep and neurophysiological studies evaluating the effect of these on sleep and sleep architecture are here reviewed.

Mild-to-Moderate Traumatic Brain Injury: A Review with Focus on the Visual System

Traumatic Brain Injury (TBI) is a major global public health problem. Neurological damage from TBI may be mild, moderate, or severe and occurs both immediately at the time of impact (primary injury) and continues to evolve afterwards (secondary injury). In mild (m)TBI, common symptoms are headaches, dizziness and fatigue. Visual impairment is especially prevalent. Insomnia, attentional deficits and memory problems often occur. Neuroimaging methods for the management of TBI include computed tomography and magnetic resonance imaging. The location and the extent of injuries determine the motor and/or sensory deficits that result. Parietal lobe damage can lead to deficits in sensorimotor function, memory, and attention span. The processing of visual information may be disrupted, with consequences such as poor hand-eye coordination and balance. TBI may cause lesions in the occipital or parietal lobe that leave the TBI patient with incomplete homonymous hemianopia. Overall, TBI can interfere with everyday life by compromising the ability to work, sleep, drive, read, communicate and perform numerous activities previously taken for granted. Treatment and rehabilitation options available to TBI sufferers are inadequate and there is a pressing need for new ways to help these patients to optimize their functioning and maintain productivity and participation in life activities, family and community.

Compounding Effects of Traumatic Brain Injury, Military Status, and Other Factors on Pittsburgh Sleep Quality Index: A Meta-analysis

INTRODUCTION

Traumatic brain injury (TBI) or concussion is a known risk factor for multiple adverse health outcomes, including disturbed sleep. Although prior studies show adverse effects of TBI on sleep quality, its compounding effect with other factors on sleep is unknown. This meta-analysis aimed to quantify the effects of TBI on subjective sleep quality in the context of military status and other demographic factors.

MATERIALS AND METHODS

A programmatic search of PubMed database from inception to June 2020 was conducted to identify studies that compared subjective sleep quality measured using Pittsburgh Sleep Quality Index (PSQI) in individuals with TBI relative to a control group. The meta-analysis included group-wise standard mean difference (SMD) and 95% CI. Pooled means and SDs were obtained for TBI and non-TBI groups with and without military service, and meta-regression was conducted to test for group effects. Exploratory analysis was performed to test for the effect of TBI, non-head injury, military status, sex, and age on sleep quality across studies.

RESULTS

Twenty-six articles were included, resulting in a combined total of 5,366 individuals (2,387 TBI and 2,979 controls). Overall, individuals with TBI self-reported poorer sleep quality compared to controls (SMD = 0.63, 95% CI: 0.45 to 0.80). Subgroup analysis revealed differences in the overall effect of TBI on PSQI, with a large effect observed in the civilian subgroup (SMD: 0.80, 95% CI: 0.57 to 1.03) and a medium effect in the civilian subgroup with orthopedic injuries (SMD: 0.40, 95% CI: 0.13 to 0.65) and military/veteran subgroup (SMD: 0.43, 95% CI: 0.14 to 0.71). Exploratory analysis revealed that age and history of military service significantly impacted global PSQI scores.

CONCLUSIONS

Poor sleep quality in TBI cohorts may be due to the influence of multiple factors. Military/veteran samples had poorer sleep quality compared to civilians even in the absence of TBI, possibly reflecting unique stressors associated with prior military experiences and the sequelae of these stressors or other physical and/or psychological traumas that combine to heightened vulnerability. These findings suggest that military service members and veterans with TBI are particularly at a higher risk of poor sleep and its associated adverse health outcomes. Additional research is needed to identify potential exposures that may further heighten vulnerability toward poorer sleep quality in those with TBI across both civilian and military/veteran populations.

The Impact of Opioid Medications on Sleep Architecture and Nocturnal Respiration During Acute Recovery From Moderate to Severe Traumatic Brain Injury: A TBI Model Systems Study

OBJECTIVES

To describe patient and clinical characteristics associated with receipt of opioid medications and identify differences in sleep quality, architecture, and sleep-related respiration between those receiving and not receiving opioid medications.

SETTING

Acute inpatient rehabilitation care for moderate to severe traumatic brain injury (TBI).

PARTICIPANTS

A total of 248 consecutive admissions for inpatient rehabilitation care following moderate to severe TBI (average age of 43.6 years), who underwent level 1 polysomnography (PSG) (average time since injury: 120 days) across 6 sites.

DESIGN

Cross-sectional, secondary analyses.

MAIN MEASURES

The PSG sleep parameters included total sleep time (TST), sleep efficiency (SE), wake after sleep onset, rapid eye movement (REM) latency, sleep staging, and arousal and awakening indices. Respiratory measures included oxygen saturation, central apnea events per hour, obstructive apnea and hypopnea events per hour, and total apnea-hypopnea index.

RESULTS

After adjustment for number of prescribed medication classes, those receiving opioid medications on the day of PSG experienced increased TST relative to those not receiving opioid medications (estimated mean difference [EMD] = 31.58; 95% confidence interval [CI], 1.9-61.3). Other indices of sleep did not differ significantly between groups. Among respiratory measures those receiving opioids on the day of PSG experienced increased frequency of central sleep apnea events during total (EMD = 2.92; 95% CI, 0.8-5.0) and non-REM sleep (EMD = 3.37; 95% CI, 1.0-5.7) and higher frequency of obstructive sleep apnea events during REM sleep (EMD = 6.97; 95% CI, 0.1-13.8). Compared with those who did not, receiving opioids was associated with lower oxygen saturation nadir during total sleep (EMD = -3.03; 95% CI, -5.6 to -0.4) and a greater number of oxygen desaturations across REM (EMD = 8.15; 95% CI, 0.2-16.1), non-REM (EMD = 7.30; 95% CI, 0.3-14.4), and total sleep (EMD = 8.01; 95% CI, 0.8-15.2) Greater total apnea-hypopnea index was observed during REM (EMD = 8.13; 95% CI, 0.8-15.5) and total sleep (EMD = 7.26; 95% CI, 0.08-14.4) for those receiving opioids.

CONCLUSION

Opioid use following moderate to severe TBI is associated with an increase in indicators of sleep-related breathing disorders, a modifiable condition that is prevalent following TBI. As sleep-wake disorders are associated with poorer rehabilitation outcomes and opioid medications may frequently be administered following traumatic injury, additional longitudinal investigations are warranted in determining whether a causal relation between opioids and sleep-disordered breathing in those following moderate to severe TBI exists. Given current study limitations, future studies can improve upon methodology through the inclusion of indication for and dosage of opioid medications in this population when examining these associations.

Assessing Sleep Architecture With Polysomnography During Posttraumatic Amnesia After Traumatic Brain Injury: A Pilot Study

BACKGROUND

Early-onset sleep disturbance is common following moderate to severe traumatic brain injury (TBI) and often emerges while patients are in posttraumatic amnesia (PTA). However, sleep disruptions during this subacute recovery phase are not well-defined, and research often utilizes indirect measures (actigraphy) that quantify sleep based on activity. This study aims to examine sleep macro-architecture and sleep quality directly with ambulatory polysomnography (PSG) and measure endogenous salivary melatonin levels for patients experiencing PTA following moderate to severe TBI.

METHOD

Participants were recruited from an inpatient TBI rehabilitation unit. Nighttime PSG was administered at the patient's bedside. Two saliva specimens were collected for melatonin testing on a separate evening (24:00 and 06:00 hours) using melatonin hormone profile test kits.

RESULTS

Of 27 patients in whom PSG was recorded, the minimum required monitoring time occurred in n =17 (adherence: 63%) at a median of 37.0 days (quartile 1 [Q1] to quartile 3 [Q3]: 21.5-50.5) postinjury. Median non-rapid eye movement (NREM) and REM sleep proportions were similar to normal estimates. Slow-wave sleep was reduced and absent in 35.3% of patients. Sleep periods appeared fragmented, and median sleep efficiency was reduced (63.4%; Q1-Q3: 55.1-69.2). Median melatonin levels at both timepoints were outside the normal range of values specified for this test (from Australian Clinical Labs).

CONCLUSION

This study reports that ambulatory PSG and salivary melatonin assessment are feasible for patients experiencing PTA and offers new insight into the extent of sleep disturbance. Further research is necessary to understand associations between PTA and sleep disturbance.

Sleep after Traumatic Brain Injury

Sleep disturbances are common after traumatic brain injury of all levels of severity, interfere with acute and long-term recovery, and can persist for years after injury. There is increasing evidence of the importance of sleep in improving brain function and recovery. Noticing and addressing sleep disturbances are important aspects of nursing care, especially for the prevention or early recognition of delirium. Nonpharmacologic interventions can improve sleep. Teaching about the importance of sleep after traumatic brain injury, promoting sleep hygiene, and multidisciplinary approaches to addressing sleep problems and improving sleep are important for recovery from traumatic brain injury.

Capture rates of comorbidity measures at inpatient rehabilitation facilities after a stroke or brain injury

BACKGROUND

Comorbidity indices have been used to represent the overall medical complexity of patient populations in clinical research; however, it is not known how well they capture the comorbidities of patients with a stroke or brain injury admitted to inpatient rehabilitation facilities (IRFs).

OBJECTIVE

To determine how well commonly used comorbidity indices capture the comorbidities of patients admitted to IRFs after a stroke or brain injury.

DESIGN

Cross-sectional, retrospective study.

SETTING

IRFs nationwide.

PARTICIPANTS

Adults from four impairment groups: (1) hemorrhagic stroke, (2) ischemic stroke, (3) nontraumatic brain injury (NTBI), and (4) traumatic brain injury (TBI).

MAIN OUTCOME MEASURES

International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM) codes were extracted from the Uniform Data System for Medical Rehabilitation (UDSMR) for IRF discharges from October 1, 2015 to December 31, 2017. The percentage of discharges captured by Deyo-Charlson, Elixhauser, and Centers for Medicare and Medicaid Services (CMS) tiers was determined, as was the percentage of comorbidities captured. These measures were also compared with respect to their ability to capture chronic medical complexity by examining the percentage of codes captured after removal of codes deemed to represent hospital complications or sequela of the admission diagnosis.

RESULTS

The percentage of discharges without at least one ICD-10-CM code captured by any index ranged from 0.3%-3.8%. The percentage of comorbidities with a prevalence exceeding 1% captured by at least one index ranged from 37.1%-43.6%. Chronic comorbidities were most likely to be captured by Elixhauser (40.7%-44.4%), followed by Deyo-Charlson (7.8%-9.6%), then CMS tiers (4.5%-6.9%). Existing comorbidity measures capture most IRF discharges related to a brain injury or stroke, whereas most medical comorbidities escape representation. Several common, functionally relevant diagnoses were not captured.

CONCLUSION

The use of comorbidity indices in the IRF neurologic injury population should account for the fact that these measures miss several common, important comorbidities.

The effect of phototherapy on sleep during acute rehabilitation after traumatic brain injury: a randomized controlled trial

Objective: To examine the impact of bright white light (BWL) exposure on sleep quality in persons with recent traumatic brain injury (TBI).Design: Randomized, controlled device-sham studySetting: 3 TBI Model System inpatient rehabilitation unitsParticipants: 131 participants (mean 40.9 years, 68% male)Intervention: Intervention group (N = 65) received BWL (1260 lux at 20 inches, 440-480 nanometers length) for 30 minutes each morning at 12-24 inches from the face. Control group (N = 66) received red light (<450 lux, no light between 440 and 480 nanometers) for the same period. Planned intervention was maximum of 10 treatments or until discharge.Main Outcome Measure: Sleep duration and quality using actigraphic recording.Results: There were no differences found between groups on the primary outcomes nor on the secondary outcomes (sleepiness, mood, cooperation with therapy).Conclusion: BWL treatment during acute rehabilitation hospitalization does not appear to impact sleep or measures commonly associated with sleep. While studies have indicated common complaints of sleep difficulties after TBI, we were unable to document an effect for phototherapy as a treatment. With growing evidence of the effect of sleep on neural repair and cognition, further study is needed to understand the nature and treatment of sleep disorders after TBI.Clinicaltrials.gov Identifier: NCT02214212.

Sleep disorders in traumatic brain injury

The purpose of the review is to collect the most relevant current literature on the mechanisms of normal sleep and sleep disorders associated with traumatic brain injury (TBI), to discuss the most frequent conditions and the evidence on their possible treatments and future research. Sleep disorders are extremely prevalent after TBI (30-84%). Insomnia and circadian rhythm disorders are the most frequent disorders among the population that has suffered mild TBI, while hypersomnolence disorders are more frequent in populations that have suffered moderate and severe TBI. The syndrome of obstructive sleep apnea and restless leg syndrome are also very frequent in these patients; and patients exposed to multiple TBIs (war veterans) are especially susceptible to sleep disorders. The treatment of these disorders requires taking into account the particularities of these patients. In conclusion, diagnosis and treatment of sleep disorders should become part of routine clinical practice and cease to be anecdotal (as it is today) in patients with TBI. In addition, it is necessary to continue carrying out research that reveals the best therapeutic approach to these patients.

Sleep disorders in traumatic brain injury

The purpose of the review is to collect the most relevant current literature on the mechanisms of normal sleep and sleep disorders associated with traumatic brain injury (TBI), to discuss the most frequent conditions and the evidence on their possible treatments and future research. Sleep disorders are extremely prevalent after TBI (30-84%). Insomnia and circadian rhythm disorders are the most frequent disorders among the population that has suffered mild TBI, while hypersomnolence disorders are more frequent in populations that have suffered moderate and severe TBI. The syndrome of obstructive sleep apnea and restless leg syndrome are also very frequent in these patients; and patients exposed to multiple TBIs (war veterans) are especially susceptible to sleep disorders. The treatment of these disorders requires taking into account the particularities of these patients. In conclusion, diagnosis and treatment of sleep disorders should become part of routine clinical practice and cease to be anecdotal (as it is today) in patients with TBI. In addition, it is necessary to continue carrying out research that reveals the best therapeutic approach to these patients.

Factors Affecting Participation in Physical Therapy During Posttraumatic Amnesia

OBJECTIVES

To examine the effect of agitation, cognitive impairment, fatigue, and pain on physical therapy participation and outcomes during posttraumatic amnesia (PTA) after traumatic brain injury (TBI).

DESIGN

Prospective longitudinal study.

SETTING

Inpatient rehabilitation hospital.

PARTICIPANTS

Participants (N=77) with moderate-to-severe TBI who were deemed to be experiencing PTA using the Westmead Post-Traumatic Amnesia Scale.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

The Pittsburgh Rehabilitation Participation Scale and time in therapy (min) were recorded twice daily after routine physical therapy sessions during PTA. The FIM-motor (select items related to physical therapy) score rated on admission and after emergence from PTA was used to calculate FIM-motor change.

RESULTS

Agitation was associated with lower participation in therapy. The presence of agitation and pain both predicted lower FIM-motor change at emergence from PTA. Higher levels of cognitive impairment and fatigue were also associated with lower participation and less time in therapy.

CONCLUSIONS

The presence of agitation, fatigue, pain, and cognitive impairment impede rehabilitation success during PTA. This study strengthens the case for implementing environmental and behavioral recommendations, such as conducting therapy earlier in the day within a familiar space (ie, on the ward) and tailoring session duration to patient needs. This is with the aim of minimizing fatigue, agitation, and pain, while promoting cognitive recovery and arousal during PTA to maximize physical gains. Further research is warranted to examine the factors associated with rehabilitation success across other therapeutic disciplines.

Sleep Supports Memory and Learning: Implications for Clinical Practice in Speech-Language Pathology

Purpose This tutorial aims to draw attention to the interactions among memory, sleep, and therapy potential and to increase awareness and knowledge in the field of speech-language pathology of the potential impact of sleep as a mediating or moderating factor in promoting therapeutic outcome. Method We highlight key findings from the literature on the cognitive neuroscience of memory, the neurophysiology of sleep, how sleep supports memory, and how sleep disruption affects memory and learning abilities in populations commonly served in speech-language pathology. Results Research increasingly points to the critical importance of sleep quality and quantity to memory and learning, and sleep disruption is linked to deficits in functional cognition that may limit our clients' ability to benefit from speech pathology interventions. Conclusions As a field dedicated to promoting memory, learning, and relearning through our interventions, any systemic factors that affect these abilities demand our attention. Although speech-language pathologists do not treat sleep disturbance, we play a critical role in recognizing the signs and symptoms of sleep disturbance and making appropriate referrals, as undiagnosed and untreated sleep disturbance can have serious impacts on success in therapeutic contexts. By considering how related factors affect memory and learning, we have the opportunity to take a whole client approach to maximizing our clients' therapy potential and functional progress.

Validity of actigraphy for nighttime sleep monitoring in hospitalized patients with traumatic injuries

STUDY OBJECTIVES

Sleep-wake disturbances are frequent among patients hospitalized for traumatic injuries but remain poorly documented because of the lack of tools validated for hospitalized patients. This study aimed to validate actigraphy for nighttime sleep monitoring of hospitalized patients with severe traumatic injuries, using ambulatory polysomnography (PSG).

METHODS

We tested 17 patients (30.4 ± 14.7 years, 16.6 ± 8.2 days postinjury) who had severe orthopedic injuries and/or spinal cord injury, with or without traumatic brain injury. When medically stable, patients wore an actigraph on a nonparalyzed arm and underwent ambulatory PSG at the bedside. Data were converted to 1-minute epochs. The following parameters were calculated for the nighttime period: total sleep time, total wake time, sleep efficiency, and number of awakenings. Epoch-by-epoch concordance between actigraphy and PSG was analyzed to derive sensitivity, specificity, and accuracy. PSG sleep parameters were compared to those obtained from four actigraphy scoring algorithms by Bland-Altman plots.

RESULTS

Sensitivity to detect sleep was ≥ 92% and accuracy was > 85% for all four actigraphy algorithms used, whereas specificity varied from 48% to 60%. The low-activity wake threshold (20 activity counts per epoch) was most closely associated with PSG on all sleep parameters. This scoring algorithm also had the highest specificity (59.9%) and strong sensitivity (92.8%).

CONCLUSIONS

Actigraphy is valid for monitoring nighttime sleep and wakefulness in patients hospitalized with traumatic injuries, with sensitivity, specificity and accuracy comparable to actigraphic recordings in healthy individuals. A scoring algorithm using a low wake threshold is best suited for this population and setting.

Optimized Sleep After Brain Injury (OSABI): A Pilot Study of a Sleep Hygiene Intervention for Individuals With Moderate to Severe Traumatic Brain Injury

Background. Disrupted sleep is common after traumatic brain injury (TBI) particularly in the inpatient rehabilitation setting where it may affect participation in therapy and outcomes. Treatment of sleep disruption in this setting is varied and largely unexamined. Objective. To study the feasibility of instituting a sleep hygiene intervention on a rehabilitation unit. Methods. Twenty-two individuals admitted to a brain injury unit were enrolled and allocated, using minimization, to either a sleep hygiene protocol (SHP) or standard of care (SOC). All participants wore actigraphs, underwent serial cognitive testing, and had light monitors placed in their hospital rooms for 4 weeks. Additionally, participants in the SHP received 30 minutes of blue-light therapy each morning, had restricted caffeine intake after noon, and were limited to 30-minute naps during the day. SHP participants had their lights out time set according to preinjury sleep time preference. Both groups were treated with the same restricted formulary of centrally acting medications. Results. Of 258 patients screened, 27 met all study inclusion criteria of whom 22 were enrolled. Nine participants in each group who had at least 21 days of treatment were retained for analysis. The protocol was rated favorably by participants, families, and staff. Actigraph sleep metrics improved in both groups during the 4-week intervention; however, only in the SHP was the change significant. Conclusions. Sleep hygiene is a feasible, nonpharmacologic intervention to treat disrupted sleep in a TBI inpatient rehabilitation setting. A larger study is warranted to examine treatment efficacy. ClinicalTrials.gov Identifier: NCT02838082.

Subacute sleep disturbance in moderate to severe traumatic brain injury: a systematic review

Objective: This systematic review evaluated subacute sleep disturbance following moderate to severe traumatic brain injury (TBI) and the impact of secondary factors such as mood or pain.Methods: A comprehensive search strategy was applied to nine databases. Inclusion criteria included: adults ≥18 years, moderate and severe TBI and within 3 months of injury. Eligible studies were critically appraised using the McMaster Quantitative Critical Review Form. Study characteristics, outcomes, and methodological quality were synthesized. This systematic review was registered with PROSPERO (Registration number: CRD42018087799).Results: Ten studies were included. Research identified early-onset sleep disturbances; characterized as fragmented sleep periods and difficulty initiating sleep. Alterations to sleep architecture (e.g. rapid eye movement sleep) were reported. Sleep disturbance appears to associate with alterations of consciousness. Sleep disturbance tended to be particularly increased during the phase of post-traumatic amnesia (PTA) (78.7%).Conclusions: There is a limited amount of research available, which has inherent measurement and sample size limitations. The gold standard for measuring sleep (polysomnography) was rarely utilized, which may affect the detection of sleep disturbance and sleep architecture. Secondary factors potentially influencing sleep were generally not reported. Further evaluation on associations between sleep and PTA is needed.

Sleep and fatigue after TBI

BACKGROUND

Whilst post traumatic brain injury fatigue (PTBIF) and sleep disturbance are common sequelae following brain injury, underlying mechanisms, and the potential for targeted interventions remain unclear.

OBJECTIVE

To present a review of recent studies exploring the epidemiology of PTBIF and sleep disturbance, the relationship and neuropsychological correlates of these issues, potential approaches to intervention, and implications for neurorehabilitation.

METHODS

A review of relevant literature was undertaken, with a focus on PTBIF relating to sleep disturbance, the neuropsychological correlates of these issues and implications for neurorehabilitation. This paper does not set out to provide a systematic review.

RESULTS

Multidimensional approaches to assessment and treatment of sleep disturbance and PTBIF are required.

CONCLUSIONS

There is a need for more robust findings in determining the complex nature of relationships between PTBIF, sleep disturbance, and correlates. Longitudinal prospective data is required to increase our understanding of the nature and course of PTBIF and sleep disturbance post TBI. Large scale clinical trials are required in evaluating the potential benefits of interventions.

Unraveling the Biopsychosocial Factors of Fatigue and Sleep Problems After Traumatic Brain Injury: Protocol for a Multicenter Longitudinal Cohort Study

Background

Fatigue and sleep problems are common after a traumatic brain injury (TBI) and are experienced as highly distressing symptoms, playing a significant role in the recovery trajectory, and they can drastically impact the quality of life and societal participation of the patient and their family and friends. However, the etiology and development of these symptoms are still uncertain.

Objective

The aim of this study is to examine the development of fatigue and sleep problems following moderate to severe TBI and to explore the changes in underlying biological (pain, brain damage), psychological (emotional state), and social (support family, participation) factors across time.

Methods

This study is a longitudinal multicenter observational cohort study with 4 measurement points (3, 6, 12, and 18 months postinjury) including subjective questionnaires and cognitive tasks, preceded by 7 nights of actigraphy combined with a sleep diary. Recruitment of 137 moderate to severe TBI patients presenting at emergency and neurology departments or rehabilitation centers across the Netherlands is anticipated. The evolution of fatigue and sleep problems following TBI and their association with possible underlying biological (pain, brain damage), psychological (emotional state), and social (support family, participation) factors will be examined.

Results

Recruitment of participants for this longitudinal cohort study started in October 2017, and the enrollment of participants is ongoing. The first results are expected at the end of 2020.

Conclusions

To the authors’ knowledge, this is the first study that examines the development of both post-TBI fatigue and sleep longitudinally within a biopsychosocial model in moderate to severe TBI using both subjective and objective measures. Identification of modifiable factors such as mood and psychosocial stressors may give direction to the development of interventions for fatigue and sleep problems post-TBI.

Trial Registration

Netherlands Trial Register NTR7162; http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=7162 (Archived by WebCite at http://www.webcitation.org/6z3mvNLuy)

International Registered Report Identifier (IRRID)

RR1-10.2196/11295

Poor sleep is linked to impeded recovery from traumatic brain injury

Study Objectives

While disruptions in sleep are common after mild traumatic brain injury (TBI), the longitudinal relationships between sleep problems and global functioning after injury are poorly understood. Here, we prospectively investigate risk for functional impairment during the first 6 months of TBI recovery based on sleep onset insomnia symptoms and short sleep.

Methods

Patients presenting to the Emergency Department (ED) at Johns Hopkins Hospital within 24 hours of head injury and evaluated for TBI were eligible for our study. Demographic and injury-related information were collected in the ED. Patients then completed in-person surveys and phone interviews to provide follow-up data on global functioning, sleep, and depressive symptoms at 1, 3, and 6 months post-injury. A total of 238 patients provided sufficient data for analysis, and hypotheses were tested using mixed effects modeling.

Results

Sleep quality and global functioning improved over the 6 months of TBI recovery, but patients were at increased risk for functional impairment when sleeping poorly (odds ratio [OR] = 7.69, p < .001). Sleep onset insomnia symptoms and short sleep both independently corresponded to poor global functioning. Functional impairment was highest among those with both insomnia and short sleep (43%-79%) compared to good sleepers (15%-25%) and those with short sleep (29%-33%) or insomnia alone (33%-64%). A bidirectional relationship between sleep quality and functioning was observed.

Conclusions

Functionally impaired patients diagnosed predominantly with mild TBI exhibit high rates of insomnia and short sleep, which may impede TBI recovery. Monitoring sleep after head injury may identify patients with poor prognoses and allow for early intervention to improve functional outcomes.

A Sub-acute Cerebral Contusion Presenting with Medication-resistant Psychosis

The most common symptoms of a cerebral contusion include headache, dizziness, concentration problems, and memory loss. Insomnia is reported by more than half of the patients and can exacerbate symptoms. A 24-year-old previously healthy male presented with psychosis, acute personality changes, auditory and visual hallucinations three weeks after falling 15 feet with concurrent head trauma. A right-sided cerebral contusion with concussion was diagnosed on initial admission with increasing homicidal and suicidal ideations after 26 hours of insomnia. The patient accomplished rest after seven days of medication-resistant insomnia with the final combination of ziprasidone and lorazepam. After one night of sleep, the patient was alert and oriented with normal mood, affect, and cognition. The insomnia appeared to exacerbate this patient’s symptoms, and an atypical insomnia treatment regimen was required to induce somnolence and restore function in this patient. The combination of this abnormal patient presentation along with the unorthodox medication regimen makes this case unique compared to other traumatic brain injury symptoms and treatments.

Change in body mass index within the first-year post-injury: a VA Traumatic Brain Injury (TBI) model systems study

OBJECTIVE

To describe change in body mass index (BMI) and weight classification 1-year post- traumatic brain injury (TBI) among Veterans and service members.

DESIGN

Prospective observational cohort study.

SETTING

VA Polytrauma Rehabilitation Centers.

PARTICIPANTS

Veterans and service members (N = 84) enrolled in VA Traumatic Brain Injury Model Systems (VA TBIMS) study with BMI scores at enrollment and 1-year post-injury.

INTERVENTIONS

N/A.

MAIN OUTCOME MEASURES

BMI scores from height and weight and weight classifications (underweight, normal weight, overweight, obese classes 1-3) defined by WHO.

RESULTS

Twenty per cent were obese at time of injury and 24% were obese at 1-year post-injury. Cross-tab analyses revealed 7% of normal weight and 24% overweight participants at time of injury as obese Class 1 one-year post-injury. Univariate models found BMI and tobacco smoking at time of injury were significant predictors of higher BMI scores 1-year post-TBI. Multivariable models found BMI at time of injury and motor functioning, were significant predictors. Preinjury BMI, tobacco smoking and PTSD symptom severity predicted change in weight category.

CONCLUSION

While obesity among service members and Veterans post-TBI is below national averages, trends in weight gain between time of injury and 1-year follow-up were observed. Implications for health promotion and chronic disease management efforts with regards to rehabilitation for injured military are discussed. List of Abbreviations: BMI, Body mass index; BRFSS, Behavioural Risk Factor Surveillance; GCS, Glasgow Coma Scale; FIM, Functional Independence Measure; NIDILRR, National Institute on Independent Living and Rehabilitation Research; PCL-C, PTSD checklist-civilian; PSTD, Post-traumatic stress disorder; VA, Veterans Affairs; VA PRC, Veterans Affairs Polytrauma Rehabilitation; VA TBIMS, Veterans Affairs TBI Model Systems.

Traumatic Brain Injury, Sleep Disorders, and Psychiatric Disorders: An Underrecognized Relationship

Traumatic brain injury (TBI) is commonplace among pediatric patients and has a complex, but intimate relationship with psychiatric disease and disordered sleep. Understanding the factors that influence the risk for the development of TBI in pediatrics is a critical component of beginning to address the consequences of TBI. Features that may increase risk for experiencing TBI sometimes overlap with factors that influence the development of post-concussive syndrome (PCS) and recovery course. Post-concussive syndrome includes physical, psychological, cognitive and sleep-wake dysfunction. The comorbid presence of sleep-wake dysfunction and psychiatric symptoms can lead to a more protracted recovery and deleterious outcomes. Therefore, a multidisciplinary evaluation following TBI is necessary. Treatment is generally symptom specific and mainly based on adult studies. Further research is necessary to enhance diagnostic and therapeutic approaches, as well as improve the understanding of contributing pathophysiology for the shared development of psychiatric disease and sleep-wake dysfunction following TBI.

Efficacy of melatonin for sleep disturbance following traumatic brain injury: a randomised controlled trial

BACKGROUND

The study aimed to determine the efficacy of melatonin supplementation for sleep disturbances in patients with traumatic brain injury (TBI).

METHODS

This is a randomised double-blind placebo-controlled two-period two-treatment (melatonin and placebo) crossover study. Outpatients were recruited from Epworth and Austin Hospitals Melbourne, Australia. They had mild to severe TBI (n = 33) reporting sleep disturbances post-injury (mean age 37 years, standard deviation 11 years; 67% men). They were given prolonged-release melatonin formulation (2 mg; Circadin®) and placebo capsules for 4 weeks each in a counterbalanced fashion separated by a 48-hour washout period. Treatment was taken nightly 2 hours before bedtime. Serious adverse events and side-effects were monitored.

RESULTS

Melatonin supplementation significantly reduced global Pittsburgh Sleep Quality Index scores relative to placebo, indicating improved sleep quality [melatonin 7.68 vs. placebo 9.47, original score units; difference -1.79; 95% confidence interval (CI), -2.70 to -0.88; p ≤ 0.0001]. Melatonin had no effect on sleep onset latency (melatonin 1.37 vs. placebo 1.42, log units; difference -0.05; 95% CI, -0.14 to 0.03; p = 0.23). With respect to the secondary outcomes, melatonin supplementation increased sleep efficiency on actigraphy, and vitality and mental health on the SF-36 v1 questionnaire (p ≤ 0.05 for each). Melatonin decreased anxiety on the Hospital Anxiety Depression Scale and fatigue on the Fatigue Severity Scale (p ≤ 0.05 for both), but had no significant effect on daytime sleepiness on the Epworth Sleepiness Scale (p = 0.15). No serious adverse events were reported.

CONCLUSIONS

Melatonin supplementation over a 4-week period is effective and safe in improving subjective sleep quality as well as some aspects of objective sleep quality in patients with TBI.

TRIAL REGISTRATION

Identifier: 12611000734965; Prospectively registered on 13 July 2011.

Sleep-Wake Disturbances After Traumatic Brain Injury: Synthesis of Human and Animal Studies

Sleep-wake disturbances following traumatic brain injury (TBI) are increasingly recognized as a serious consequence following injury and as a barrier to recovery. Injury-induced sleep-wake disturbances can persist for years, often impairing quality of life. Recently, there has been a nearly exponential increase in the number of primary research articles published on the pathophysiology and mechanisms underlying sleep-wake disturbances after TBI, both in animal models and in humans, including in the pediatric population. In this review, we summarize over 200 articles on the topic, most of which were identified objectively using reproducible online search terms in PubMed. Although these studies differ in terms of methodology and detailed outcomes; overall, recent research describes a common phenotype of excessive daytime sleepiness, nighttime sleep fragmentation, insomnia, and electroencephalography spectral changes after TBI. Given the heterogeneity of the human disease phenotype, rigorous translation of animal models to the human condition is critical to our understanding of the mechanisms and of the temporal course of sleep-wake disturbances after injury. Arguably, this is most effectively accomplished when animal and human studies are performed by the same or collaborating research programs. Given the number of symptoms associated with TBI that are intimately related to, or directly stem from sleep dysfunction, sleep-wake disorders represent an important area in which mechanistic-based therapies may substantially impact recovery after TBI.

Natural History of Headache Five Years after Traumatic Brain Injury

Headache is one of the most frequently reported symptoms following traumatic brain injury (TBI). Little is known about how these headaches change over time. We describe the natural history of headache in individuals with moderate to severe TBI over 5 years after injury. A total of 316 patients were prospectively enrolled and followed at 3, 6, 12, and 60 months after injury. Individuals were 72% male, 73% white, and 55% injured in motor vehicle crashes, with an average age of 42. Pre-injury headache was reported in 17% of individuals. New or worse headache prevalence remained consistent with at least 33% at all time points. Incidence was >17% at all time points with first report of new or worse headache in 20% of participants at 60 months. Disability related to headache was high, with average headache pain (on 0-10 scale) ranging from 5.5 at baseline to 5.7 at 60 months post-injury, and reports of substantial impact on daily life across all time points. More than half of classifiable headaches matched the profile of migraine or probable migraine. Headache is a substantial problem after TBI. Results suggest that ongoing assessment and treatment of headache after TBI is needed, as this symptom may be a problem up to 5 years post-injury.

Sleep Features on Continuous Electroencephalography Predict Rehabilitation Outcomes After Severe Traumatic Brain Injury

OBJECTIVE

Sleep characteristics detected by electroencephalography (EEG) may be predictive of neurological recovery and rehabilitation outcomes after traumatic brain injury (TBI). We sought to determine whether sleep features were associated with greater access to rehabilitation therapies and better functional outcomes after severe TBI.

METHODS

We retrospectively reviewed records of patients admitted with severe TBI who underwent 24 or more hours of continuous EEG (cEEG) monitoring within 14 days of injury for sleep elements and ictal activity. Patient outcomes included discharge disposition and modified Rankin Scale (mRS).

RESULTS

A total of 64 patients underwent cEEG monitoring for a mean of 50.6 hours. Status epilepticus or electrographic seizures detected by cEEG were associated with poor outcomes (death or discharge to skilled nursing facility). Sleep characteristics were present in 19 (30%) and associated with better outcome (89% discharged to home/acute rehabilitation; P = .0002). Lack of sleep elements on cEEG correlated with a poor outcome or mRS > 4 at hospital discharge (P = .012). Of those patients who were transferred to skilled nursing/acute rehabilitation, sleep architecture on cEEG associated with a shorter inpatient hospital stay (20 days vs 27 days) and earlier participation in therapy (9.8 days vs 13.2 days postinjury). Multivariable analyses indicated that sleep features on cEEG predicted functional outcomes independent of admission Glasgow Coma Scale and ictal-interictal activity.

CONCLUSION

The presence of sleep features in the acute period after TBI indicates earlier participation in rehabilitative therapies and a better functional recovery. By contrast, status epilepticus, other ictal activity, or absent sleep architecture may portend a worse prognosis. Whether sleep elements detected by EEG predict long-term prognosis remains to be determined.

The Relationship Between Sleep-Wake Cycle Disturbance and Trajectory of Cognitive Recovery During Acute Traumatic Brain Injury

OBJECTIVE

Following traumatic brain injury, both sleep dysfunction and cognitive impairment are common. Unfortunately, little is known regarding the potential associations between these 2 symptoms during acute recovery. This study sought to prospectively examine the relationship between ratings of sleep dysfunction and serial cognitive assessments among traumatic brain injury acute neurorehabilitation admissions.

METHODS

Participants were consecutive admissions to a free-standing rehabilitation hospital following moderate to severe traumatic brain injury (Median Emergency Department Glasgow Coma Scale = 7). Participants were assessed for sleep-wake cycle disturbance (SWCD) and cognitive functioning at admission and with subsequent weekly examinations. Participants were grouped on the basis of presence (SWCD+) or absence (SWCD-) of sleep dysfunction for each examination; groups were equivalent on demographic and injury variables. Individual Growth Curve modeling was used to examine course of Cognitive Test for Delirium performance across examinations.

RESULTS

Individual Growth Curve modeling revealed a significant interaction between examination number (ie, time) and SWCD group (β = -4.03, P < .001) on total Cognitive Test for Delirium score. The SWCD+ ratings on later examinations were predicted to result in lower Cognitive Test for Delirium scores and greater cognitive impairment over time.

CONCLUSIONS

This study has implications for improving neurorehabilitation treatment, as targeting sleep dysfunction for early intervention may facilitate cognitive recovery.

Incidence, Characterization, and Predictors of Sleep Apnea in Consecutive Brain Injury Rehabilitation Admissions

OBJECTIVE

To prospectively examine the incidence and risk factors for sleep apnea in consecutive brain injury rehabilitation admissions.

SETTING

Inpatient neurorehabilitation hospital.

PARTICIPANTS

Participants (n = 86) were consecutive neurorehabilitation admissions.

DESIGN

Retrospective analysis of prospectively collected data.

MAIN MEASURES

Polysomnography.

RESULTS

Half (49%) of the sample was diagnosed with sleep apnea. For the full sample, univariate logistic regression revealed age (odds ratio: 1.08; 95% confidence interval: 1.04-1.11) and hypertension (odds ratio: 7.77; 95% confidence interval: 2.81-21.47) as significant predictors of sleep apnea diagnosis. Results of logistic regression conducted within the traumatic brain injury group revealed age (odds ratio: 1.07; 95% confidence interval: 1.02-1.13) as the only significant predictor of apnea diagnosis after adjustment for other variables. Hierarchical generalized linear regression models for the prediction of apnea severity (ie, apnea-hypopnea index found that Functional Independence Measure Cognition Score (P = .01) and age (P < .01) were significant predictors. Following adjustment for all other terms, only age (P < .01) remained significant.

CONCLUSION

Sleep apnea is prevalent in acute neurorehabilitation admissions and traditional risk profiles for sleep apnea may not effectively screen for the disorder. Given the progressive nature of obstructive sleep apnea and morbidity associated with even mild obstructive sleep apnea, early identification and intervention may address comorbidities influencing acute and long-term outcome.

EEG slow waves in traumatic brain injury: Convergent findings in mouse and man

OBJECTIVE

Evidence from previous studies suggests that greater sleep pressure, in the form of EEG-based slow waves, accumulates in specific brain regions that are more active during prior waking experience. We sought to quantify the number and coherence of EEG slow waves in subjects with mild traumatic brain injury (mTBI).

METHODS

We developed a method to automatically detect individual slow waves in each EEG channel, and validated this method using simulated EEG data. We then used this method to quantify EEG-based slow waves during sleep and wake states in both mouse and human subjects with mTBI. A modified coherence index that accounts for information from multiple channels was calculated as a measure of slow wave synchrony.

RESULTS

Brain-injured mice showed significantly higher theta:alpha amplitude ratios and significantly more slow waves during spontaneous wakefulness and during prolonged sleep deprivation, compared to sham-injured control mice. Human subjects with mTBI showed significantly higher theta:beta amplitude ratios and significantly more EEG slow waves while awake compared to age-matched control subjects. We then quantified the global coherence index of slow waves across several EEG channels in human subjects. Individuals with mTBI showed significantly less EEG global coherence compared to control subjects while awake, but not during sleep. EEG global coherence was significantly correlated with severity of post-concussive symptoms (as assessed by the Neurobehavioral Symptom Inventory scale).

CONCLUSION AND IMPLICATIONS

Taken together, our data from both mouse and human studies suggest that EEG slow wave quantity and the global coherence index of slow waves may represent a sensitive marker for the diagnosis and prognosis of mTBI and post-concussive symptoms.

Delirium after a traumatic brain injury: predictors and symptom patterns

BACKGROUND

Delirium in traumatic brain injury (TBI) is common, may be predictable, and has a multifaceted symptom complex. This study aimed to examine: 1) the sum score of Glasgow Coma Scale (GCS) and if its component scores could predict delirium in TBI patients, and 2) the prominent symptoms and their courses over the first days after TBI.

METHODS

TBI patients were recruited from neurosurgical ward inpatients. All participants were hospitalized within 24 hours after their TBI. Apart from the sum score of GCS, which was obtained at the emergency department (ED), the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, diagnostic criteria for delirium were applied daily. The severity of delirium symptoms was assessed daily using the Delirium Rating Scale - Revised-98 (DRS-R-98).

RESULTS

The participants were 54 TBI patients with a mean GCS score of 12.7 (standard deviation [SD] =2.9). A total of 25 patients (46.3%) met the diagnosis of delirium and had a mean age of 36.7 years (SD =14.8). Compared with 29 non-delirious patients, 25 delirious patients had a significantly lower mean GCS score (P=0.04), especially a significantly lower verbal component score (P=0.03). Among 18 delirious patients, four symptoms of the DRS-R-98 cognitive domain (orientation, attention, long-term memory, and visuospatial ability) were moderate symptoms (score ≥2) at the first day of admission. After follow-up, three cognitive (orientation, attention, and visuospatial ability) and two noncognitive symptoms (lability of affect and motor agitation) rapidly resolved.

CONCLUSION

Almost half of patients with mild to moderate head injuries may develop delirium in the first 4 days after TBI. Those having a low GCS score, especially the verbal component score, at the ED were likely to have delirium in this period. Most cognitive domains of delirium described in the DRS-R-98 were prominent within the first 4 days of TBI with delirium. Three cognitive and two noncognitive symptoms of delirium decreased significantly.

Evolution of severe sleep-wake cycle disturbances following traumatic brain injury: a case study in both acute and subacute phases post-injury

Background

Sleep-wake disturbances are frequently reported following traumatic brain injury (TBI), but they remain poorly documented in the acute stage of injury. Little is known about their origin and evolution.

Case presentation

This study presents the case of a patient in the acute phase of a severe TBI. The patient was injured at work when falling 12 m into a mine and was hospitalized in the regular wards of a level I trauma centre. From days 31 to 45 post-injury, once he had reached a level of medical stability and continuous analgosedation had been ceased, his sleep-wake cycle was monitored using actigraphy. Results showed significant sleep-wake disturbances and severe sleep deprivation. Indeed, the patient had an average nighttime sleep efficiency of 32.7 ± 15.4 %, and only an average of 4.8 ± 1.3 h of sleep per 24-h period. After hospital discharge to the rehabilitation centre, where he remained for 5 days, the patient was readmitted to the same neurological unit for paranoid delusions. During his second hospital stay, actigraphy recordings resumed from days 69 to 75 post-injury. A major improvement in his sleep-wake cycle was observed during this second stay, with an average nighttime sleep efficiency of 96.3 ± 0.9 % and an average of 14.1 ± 0.9 h of sleep per 24-h period.

Conclusion

This study is the first to extensively document sleep-wake disturbances in both the acute and subacute phases of severe TBI. Results show that prolonged sleep deprivation can be observed after TBI, and suggest that the hospital environment only partially contributes to sleep-wake disturbances. Continuous actigraphic monitoring may prove to be a useful clinical tool in the monitoring of patients hospitalized after severe TBI in order to detect severe sleep deprivation requiring intervention. The direct impact of sleep-wake disturbances on physiological and cognitive recovery is not well understood within this population, but is worth investigating and improving.

Electronic supplementary material

The online version of this article (doi:10.1186/s12883-016-0709-x) contains supplementary material, which is available to authorized users.

EEG for Diagnosis and Prognosis of Acute Nonhypoxic Encephalopathy: History and Current Evidence

The term encephalopathy encompasses a wide variety of complex syndromes caused by a large number of different toxic, metabolic, infectious, and degenerative derangements. Acute encephalopathy typically presents with a fluctuating course involving alteration of mental status or confusion and decreased (or rarely increased) motor activity. There usually are lethargy, cognitive impairment, altered memory and mental processing of information, and disturbed sleep-wake cycles. Encephalopathy mainly occurs in the elderly and is frequently encountered in intensive care units and postoperatively. Despite new diagnostic procedures and advances in intensive medical care, acute encephalopathy constitutes a significant cause of morbidity and mortality in hospitalized patients. EEG enables rapid bedside electrophysiological monitoring providing dynamic real-time information on neocortical brain activity and dysfunction. Hence, EEG complements clinical and neuroimaging assessments of encephalopathic patients. Progressive slowing of EEG background activity with increasing cerebral compromise, the emergence of episodic electrographic transients, seizures, and decreased EEG reactivity to external stimuli provide important diagnostic and prognostic information. The aim of this review was to provide a comprehensive overview of the current evidence for the diagnostic and prognostic value of EEG in adult intensive care unit patients with acute nonhypoxic encephalopathy.